The present disclosure relates to inhalation therapy and more particularly to aerosol-producing means in the form of an improved nebulizer for attachment to a cartridge.
As indicated in U.S. Pat. No. 3,711,721, issued Nov. 13, 1973, inhalation therapy is the medical art of treating with oxygen or a mixture of oxygen and air having a high moisture content. Several classes of devices, including atomizers and humidifiers, are adapted for effecting such treatments. With respect to atomizers, or nebulizers as they are often called, a heretofore known system for inhalation therapy comprises a container for pure water which has means enabling operation of the container in one of several modes. An adapter fitting, comprised of a venturi-type member, when associated with the enabling means, adapts the container as a nebulizer reservoir and by itself provides nebulized water in the sense that small droplets of water are carried by the oxygen. A type of improved venturi can be seen from U.S. Pat. No. 3,915,386 issued Oct. 28, 1975. This just mentioned patent and the aforementioned patent are owned by the same assignee as in the present application.
In U.S. patent application Ser. No. 569,490 filed Apr. 18, 1975 of Kenneth G. Miller entitled DISPOSABLE CARTRIDGE HUMIDIFIER, now abandoned and the continuation therefore Ser. No. 826,119, filed Aug. 19, 1977, there is therein disclosed an ingenious cartridge humidifier. The subject matter of these applications are incorporated by reference. The applicant discloses an elongated generally cylindrical cartridge. It has a bottom cap and a top cap, both of which may be constructed of plastic. The two caps are joined by a cylindrical body portion which, to obtain good heat exchange properties, is constructed of a metal, such as aluminum. An electrical heater is provided which has a large bore therethrough into which the aforementioned cartridge is positioned and retained. Suitable tnermostatic controls are provided. Internally with respect to both the bottom cap and the cylindrical body portion cylindrical capillary active member is provided with a diameter sufficient to be in essential contact with the inner wall of the body portion whereby the capillary active member is in excellent heat exchange position with the heater. While the cartridge may be supplied with a fixed quantity of water for humidification it has been found to be particularly efficacious to supply water in a replenishable manner from a supply reservoir which may be an inverted bottle of water. The bottle and the heater may be suitably bracketed together whereby the entire thusly constructed unit may be suitably mounted. The bottom of the cartridge and the bottle containing a supply of water are fluidly connected by suitable egress and ingress ports and a connecting tube to provide an inverted siphon to continuously supply water from the bottle to the cartridge as it is removed therefrom. The water in the cartridge wets the capillary active member to thereby provide a large area for evaporating water than would be possible if the member were not present. The upper cap is provided with a concentrically tube to which a conduit supplying oxygen or air under pressure is supplied. The said tube has a downwardly depending extension that extends concentrically into the mentioned body portion but terminates above the level of the supplied water. In this manner the supplied gas is directed downwardly into the aforementioned body portion. The top cap is provided with an egress port which is located transverse to the axis of the cartridge. The port is connected to flexible conduit which is designed to distribute the humidified gas to a patient. The egress port is in communication with an annular space around the mentioned downward extending tube of the upper cap. In this manner the gases are first directed downwardly through the said tube and then upwardly through the mentioned annular space to the egress port.
While this arrangement of ports has been found to be enormously useful in supplying high volume of humidified gases to a patient, it has been found to be somewhat deficient under some occasions when even larger quantities of moisture must be distributed to the patient wherein the gas has also been warmed so that it is more readily acceptable by the patient and is also somewhat more beneficial.